There has been known a power supply managing technique which switches an own apparatus from a power supply-on state to a power supply-off state on a condition that a power supply-off command is received. Here, the power supply-on state refers to a state where power is supplied to constitutional elements of the apparatus, and the power supply-off state refers to a state where power is supplied to only a constitutional element for receiving a power supply-on command and is not supplied to the other constitutional elements.
For example, JP-A-2004-262065 describes an image forming apparatus in which, when a user turns off a power supply switch, various controllers perform power supply-off control. The image formation apparatus has two controllers, and when the image forming apparatus switches from the power supply-on state to the power supply-off state, each controller performs shut down processing and the power supply is interrupted after the shut down processing of all the controllers is completed.